Antioxidative compounds

Antiozonants (qv) prevent or reduce polymer degradation by the active ozone molecule. Some antioxidant compounds, such as the /)i7n7-phenylenediamines, are excellent as antiozonants (36). The protection by these compounds is thought to be either a reaction with the ozone before it can react with the surface of the mbber or an aid in reuniting chains severed by ozone (37). 

Trommer, H. Neubert, R.H. (2005). The examination of polysaccharides as potential antioxidative compounds for topical administration using a lipid model system. International Journal of Pharmaceutics, Vol. 298, No. 1, 0uly 2005), pp.153-163, ISSN 0378-5173. 

In their review some years ago, Reddy and Rao (1986) cited several lines of evidence for peroxisome-proliferation-mediated oxidative stress being associated with hepatocarcinogenesis. They mentioned the sustained increase in hydrogen peroxide production, the detectable increased levels of hydrogen peroxide in the livers of treated animals, increased lipid peroxidation associated with treatment and marked inhibition of hepatocarcinogenesis by antioxidant compounds. However, definitive studies remain to be carried out. 

Carbonaro M, Mattera M, Nicoli S, Bergamo P and Cappelloni M (2002), Modulation of antioxidant compounds in organic vs conventional fruit (peach, Prunus persica L., and pear, Pyrus communis L.) , J Agric Food Chem, 50, 5458-5462. 

Wang S Y and Lin H S (2003), Compost as a soil supplement increases the level of antioxidant compounds and oxygen radical absorbance capacity in strawberries , J Agric Food Chem, 51, 6844—6850. 

Mezadri T, Villano D, Fernandez-Pachon MS, Garcia-Parrilla MC and Troncoso AM. 2008. Antioxidant compounds and antioxidant activity in acerola (Malpighia emarginata DC.) fruits and derivatives. J Food Comp Anal 21(4) 282-290. 

Because of the easily oxidizable structure of the polyphenols previously described, many studies have been published about the enzymatic degradation of these antioxidant compounds. This chapter exhaustively reviews the main publications concerning the degradation of this type of antioxidant compound by several enzymes. 

Gpbczynski P and Kmiecik W. 2007. Effects of traditional and modified technology, in the production of frozen cauliflower, on the contents of selected antioxidative compounds. Food Chem 101 229-235. 

This method is also used to measure ex vivo low-density lipoprotein (LDL) oxidation. LDL is isolated fresh from blood samples, oxidation is initiated by Cu(II) or AAPH, and peroxidation of the lipid components is followed at 234 nm for conjugated dienes (Prior and others 2005). In this specific case the procedure can be used to assess the interaction of certain antioxidant compounds, such as vitamin E, carotenoids, and retinyl stearate, exerting a protective effect on LDL (Esterbauer and others 1989). Hence, Viana and others (1996) studied the in vitro antioxidative effects of an extract rich in flavonoids. Similarly, Pearson and others (1999) assessed the ability of compounds in apple juices and extracts from fresh apple to protect LDL. Wang and Goodman (1999) examined the antioxidant properties of 26 common dietary phenolic agents in an ex vivo LDL oxidation model. Salleh and others (2002) screened 12 edible plant extracts rich in polyphenols for their potential to inhibit oxidation of LDL in vitro. Gongalves and others (2004) observed that phenolic extracts from cherry inhibited LDL oxidation in vitro in a dose-dependent manner. Yildirin and others (2007) demonstrated that grapes inhibited oxidation of human LDL at a level comparable to wine. Coinu and others (2007) studied the antioxidant properties of extracts obtained from artichoke leaves and outer bracts measured on human oxidized LDL. Milde and others (2007) showed that many phenolics, as well as carotenoids, enhance resistance to LDL oxidation. 

This assay, developed by Taga and others (1984), is based on the coupled oxidation of (3-carotene and linoleic acid. The method estimates the relative ability of antioxidant compounds to scavenge the radical of linoleic acid peroxide (LOO ) that oxidizes (3-carotene in the emulsion phase. 

Gorinstein S, Cvikrova M, Machackova I, Haruenkit R, Park YS, Jung ST, Yamamoto K, Martinez Ayala AL, Katrich E and Trakhtenberg S. 2004. Characterization of antioxidant compounds in Jaffa sweeties and white grapefruits. Food Chem 84(4) 503-510. 

Compartmentation means both spatial separation of potentially harmful but essential compounds (e.g., storage of iron in ferritin) and cell- and tissue-specific distribution of antioxidative compounds, and it serves to prevent uncontrolled oxidation. 

Their detector allowing quantification of the generated species and indicating changes in the measured signal as a response to the presence of antioxidative compounds... 

PI Antioxidative compounds were isolated from the 50% methanol extract of dried leaves of Celastrus hindsii. (From Ly et ah, 2006)... 

Simoes-Pires, C. A., Queiroz, E. F., Henriques, A. T., and Hostettmann, K., Isolation and on-hne identification of antioxidant compounds from three Baccharis species by HPLC-UV-MS/MS with post-column derivatisation. Phytochemical Analysis 16(5), 307-314, 2005. 

CA 46, 1768 (1952). An easily combustible mixture suitable as fuel for incendiary bombs and grenades, flame throwers, etc. Consists of 7-14% volatile hydrocarbon fuel such as gasoline, and 93 to 86% of soap-type gelling agent, which is composed of Al oleate 50-75, Al stearate 25-50, to which is added about 1% of oxy-aromatic antioxident compound... 

Most flavonoids are potent antioxidant compounds. Several flavonoids possess anti-inflammatory, antihepatotoxic, antimmour, antimicrobial and antiviral properties. Many traditional medicines and medicinal plants contain flavonoids... 

Antioxidant chemicals A number of intracellular reducing agents, such as ascorbate (see p. 375), vitamin E (see p. 389), and P-carotene (see p. 380), are able to reduce and, thus, detoxify oxygen intermediates in the laboratory. Consumption of foods rich in these antioxidant compounds has been correlated with a reduced risk for certain types of cancers, as well as decreased... 

Oxidation results from the interactions between atmospheric oxygen and the double bonds of unsaturated fatty acids. Several parameters can catalyze lipid oxidation, while others can prevent or slow down the reactions. Metals, light, moisture and heat can all enhance oxidation, while antioxidant compounds (e.g., BHT and vitamin E) can be utilized to retard oxidation. Oxidation of double bonds leads to intermediate peroxides that eventually break down into a variety of stable compounds. 

Ke, P.J., Nash. D.M., and Ackman, R.G. 1977. Mackerel skin lipids as an unsaturated fat model system for the determination of antioxidative potency of TBHQ and other antioxidant compounds. J. Am. Oil Chem. Soc. 54 417-420. 

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